1. Multifunctional measuring platform for investigations parameters of metal-dielectric structures
V.A. Katrich, D.V. Mayboroda, S.A. Pogarsky, I.I. Saprykin
automation complex, dielectric image guide, energetic characteristics
Vestnik KhNU ¹712 Pages. 21-24
The multifunctional automation measuring platform for ultra high frequencies parameters definition has been de- signed. The basis of this complex is the controlled mechanical platform which allows to measure the field amplitudes along two orthogonal coordinates. The processing of measuring date realizes with the help of special software. The measuring of energetic characteristics of radiating module based on dielectric image guide has been carried out
2. Stochastic fields optimal processing in MPSAR
multiposition system, synthetic aperture, stochastic model, combined estimation
Vestnik KhNU ¹712 Pages. 30-32
This paper represents optimal combined estimation algorithm in multiposition synthetic aperture radar as- signed for estimation of the parameters, contained in correlation function of the complex scattering coefficient; the most important special cases were presented
3. Telemetering methods, devices and their application in vertebrology
S.N. Kulish, O.Y. Kagan
radiotelemetring research, transmitter, radio channel, implant devices, spine, impellent segments
Vestnik KhNU ¹712 Pages. 33-36
In the given job the review and the analysis of existing telemetering methods of research and diagnostics of various diseases in medicine is resulted. It is offered to use means of radiotelemetering research for registration of mechanical parameters arising on contact and lateral surfaces of impellent segments of a backbone. The block diagram of multichannel telemetering system is resulted and the basic requirements shown to this system are described
4. Longitudinal slot radiators cut in circular waveguide
E.Y. Belogurov, V.A. Katrich, V.A. Lyaschenko
circular waveguide, axial slot, electromagnetic waves, radiation, slot antennas
Vestnik KhNU ¹712 Pages. 37-41
Using method of magnetomotive forces investigations of behaviors of longitudinal slots that were cut in wall of the circular waveguide were carried out. Expressions of internal self-admittance and transfer conductance were de- rived. The possibility of creation of a tapered illumination that forms radiation pattern with low side lobes on long slot cut in circular waveguide was shown
5. Integral representation of green function in parallel-plate and rectangular waveguide, and in resonator as well
V.A. Katrich, F.S. Novokhatsky
waveguides, Green function, fundamental solution, radial function, elliptical teta- function, image method, calculus of residues, integral transformation, grating, formal variative
Vestnik KhNU ¹712 Pages. 67-70
The known results connected with Green function representation by elliptical theta-function are generalized. New representations of Green function for some widely used types of waveguides are obtained. Earlier, these Green functions are presented either in form of series with nonuniform convergence or in form of integrals containing Hancel functions, which are reduced to asymptotic expressions in far zone. On this work integral representations of Green functions are obtained for Cases where the quadrature formula exists. The method of analytical continuation with parameter is applied
6. Features of forming patterns of planar antennas arrays
A.A. Bulgakova, N.N. Gorobets, V.A. Katrich, V.A. Lyashenko
planar arrays, pattern, sidelobes, radiator elements, interference maximums triangular grid
Vestnik KhNU ¹712 Pages. 71-75
Computer analysis results of an influence of a radiating aperture form of the planar array on its pattern have been presented. It is shown that there is dependence of levels of interference lobes and also near and far sidelobes of pattern in one of main positions of observation planes on number and radiators in plane which is orthogonal to main observation plane
7. Modelling of holographic radar with discrete and continuous aperture
B. Kochetov, A. Butrym
holographic radar, method of maximum likelihood, point scatter
Vestnik KhNU ¹712 Pages. 76-79
Images of a point scatter are investigated that are obtained with a model of holographic radar with discrete and continuous aperture, under illumination with planar or spherical wave. Main features of the scatter image are revealed and their dependence on parameters of the radar (aperture dimensions, elements spacing in the gratings, type of illumination) are studied
8. The influence of the inner chanal of a periodic iris-loaded circular waveguide concerning its eigenmode mutual transformations
He Shi, S.K. Katenev, S.N. Shulga
dispersion, Brillouin diagram, mode transformation
Vestnik KhNU ¹712 Pages. 80-83
The mutual eigenmode transformations are considered of a periodic iris-loaded circular waveguide against variations or its inner radius, using BriUouin diagram characteristics. The specific features of the waveguide regular and periodicity modes of Eo,and asymmetric waves are pointed out
9. The finite difference scheme in time domain (FDTD) and analytical solution to Klein-Gordon equation
Yu Zheng, B. A. Kochetov, A.Yu Butrym
Klein-Gordon equation, FDTD, finite difference equation, Laguerre impulse
Vestnik KhNU ¹712 Pages. 91-94
A finite difference algorithm for solving inhomogeneous Kleine-Gordon equation in Time Domain with arbitrary waveform pointwise source is considered in the paper. The numerical results were compared with analytical so-lution that was obtained using Laplace transformation in a convolution operator form. The results confirm validity of both the obtained numerical algorithm and the analytical solution
10. ELECTRODYNAMIC MODELING OF COMPOSITE MEDIA WITH SIMALTENEOUSLY NEGATIVE REAL PARTS OF PERMITTIVITY AND PERMEABILITY
S.N. Shulga, I.E. Khodasevych
composite media, thin-wire resonance inclusions, permittivity, permeability, scattering of electromagnetic waves
Vestnik KhNU ¹756 Pages. 38-41
This paper presents physical and mathematical model and investigation of electromagnetic properties of composite material made of straight and curved conducting resonance inclusions placed into isotropic media and forming periodic lattice. The effective constitutive parameters of the composite material are found. It is revealed that on resonance frequency real parts of permittivity and permeability of such media can assume simultaneously negative values. The problem of reflection and transmission of plane electromagnetic wave through a sequence of layers made of such composite material is solved, numerical results are presented
11. INFLUENCE of ENVIRONMENT ON the FIELD, SCATTERING ON the LATTICE WITH LAYER, AT ANY FALL of the WAVE
A.I. Adonina, V.B. Khokh
lattice, environment, dielectric, a stream of capacity, method of Riman-Hilbert problem
Vestnik KhNU ¹756 Pages. 51-56
The decision of a task in view is carried out for Å and Í the fields appropriate to two subsystems on which the system of the equations of the Maxwell for environments is divided. Integrated characteristics of a field are determined from the decision of systems of the linear algebraic equations received by a method of method of Riman-Hilbert problem , for a case when the smallest parameter decreases in inverse proportion to a square n->infinity. Programs (fort) with construction of diagrams are made. The analysis of the diagrams in part given in work, allows to establish influence of parameters of structure and corners of fall of a wave on anomalies in an absent-minded field for each concrete case
12. THE INFLUENCE OF MUTUAL COUPLING ON RADIATION CHARACTERISTICS OF ANTENNA ARRAY FOR VIDEOPULSE EXCITATION
mutual coupling, finite TSA arrays, Van-Atta array, videopulse
Vestnik KhNU ¹756 Pages. 57-60
In paper antenna array from finite number of the elements, which are exited by a videopulse is observed. The model for calculation of radiated fields of antenna taking consideration of mutual coupling between elements is proposed. A directed characteristics analysis of the retrodirected systems, Van-Atta array, from finite number of elements and wave form of radiated and reradiated signals are investigated in case of excitation by a videopulse. Recommendations to decrease mutual coupling is proposed. The case of useful influence on characteristics of a radiated pulse signal is considered
13. The analytical method for a periodical sequence of the alternate grates of dielectric bars investigate
thick grate of dielectric bars, anisotropic layer, periodic structure, propagation constant, scattering coefficients
Vestnik KhNU ¹756 Pages. 79-82
The electromagnetic properties of a finite periodic sequence of the thick grates of dielectric bars are investigated. The grates are identified with the homogeneous anisotropic layer of an appropriate thickness, in order to generalize, the layers which anisotropic properties of both permittivity and permeability are employed. The sequence scattering .coefficients are determined in analytical form using the circuit theory and the matrix functions techniques. Physical analysis of the frequency, angle and interference dependencies of the scattered field amplitude is carried out.
14. The Gaussian beam scattering on the bounded sequence of alternate grates of dielectric bars
V.B. Kazanskiy, V.R. Tuz, D.V. Yudintsev
Gaussian beam, thick grate of dielectric bars, anisotropic layer, periodic structure
Vestnik KhNU ¹756 Pages. 83-86
The Gaussian beam scattering on bounded periodical sequence of thick grates of dielectric bars are investigated. Identification of discrete structure with appropriate thickness homogeneous anisotropic layer was carried out for define sequence basic element transmission matrix. The sequence scattering coefficients were written down via Mougin polynomials. The effects of form distortion, beam splitting into several beams, side shift of beam axe were shown. Their correlation with scattering coefficients phase and module angle dependence of separate grates was established.
15. Electrons in superlattice with continuous conduction band edge
M.V. Klymenko, S.I. Petrov
superlattice, effective mass, Bragg effect, carriers confinement
Vestnik KhNU ¹756 Pages. 91-96
In this paper, the energy spectrum of electrons is investigated for the superlattice with continuous conduction band edge. The comparison with conventional superlattice has been realized. It is shown that in the investigated structure the energy spectrum has band structure which is caused by periodic position-dependent effective-mass. Moreover, position-dependent effective-mass leads to additional effective potential. The Bragg reflection for electrons in ballistic limit can be observed in the superlattice with continuous conduction band edge. It can be used for effective Bragg confinement of carriers. For the first time the investigations have been carried out for the case when the superlattice without band offsets has finite number of periods. The obtained results shed light on new applications of the investigated structures for THz frequency range
16. SPECKLE – INTERFEROMETRICIAN METHOD FOR ANEMOMETRICIAN OF TURBULENT STREAMS
G.N. Dolya, À.N. Katunin, Ê.V. Sadovy, S.I. Shmatkov
, speckle – interferometrician, anemometrician, speckle – painting, light-reflecting coverage
Vestnik KhNU ¹756 Pages. 118-122
In this paper is researched the possibility of the use of the modified speckle – interferometrician method for anemometrician of turbulent streams. It is developed laser anemometer on the basis of the modified speckle – interferometrician method at the applications of light-reflecting coverage. Is dependence of increase of border frequency of signal’s spectrum at growth of speed of stream transversal to the ray. Dependence of spectrum of fluctuations the adopted signal on the degree of the brought distortions in at a different temperature of turbulent stream is explored
17. CALCULATION and EXPERIMENTAL MEASUREMENT OF ANODE BLOCKS PARAMETERS OF MAGNETRONS
K.M. Basrawi, G.I. Churyumov
magnetron, anode block, Q quality factor, loaded Q factor, equivalent capacity, mode
Vestnik KhNU ¹756 Pages. 132-138
In this paper the outcomes of calculation and experimental measurements of cold parameters of the pulse and continuous X - range magnetrons are presented. The measuring and calculation techniques of equivalent capacities of the anode blocks of the magnetrons as well as Q quality factor, loaded Q factor and external Q factors of the resonant system for main N/2 - mode and nearest N/2 -1 and N/2 -2 -modes is given
18. Features of the forest radio emissi
L.M. Atroshenko, K.P. Gaikovich, N.N. Gorobets, V.N. Gorobets
radio emission, a forest
Vestnik KhNU ¹806 Pages. 8-13
Dielectric permeability of sheet plates of deciduous breeds of trees, dependence of the level of own wood signal from its projective covering, temperature distinctions, diffraction of radiowaves and their plural reflections in a crone of trees are investigated.
19. THE H10 WAVE SCATTARING BY THE THIN VARIABLE RADIUS IMPEDANCE VIBRATOR IN A
Nesterenko, E.Y. Belogurov, V.A. Katrich, V.I Kijko
impedance vibrator, biconical vibrator, distributed surface impedance, rectangular waveguide, the method of induced electromotive forces
Vestnik KhNU ¹806 Pages. 14-17
The problem of the fundamental wave scattering by the thin variable radius impedance vibrator arbitrary situated in a rectangular waveguide was solved. Calculations were carried out and energetic characteristics of such structures were plotted
20. Resonance phenomena occurring as a thin refractive cylinder diffracts the hertzian wave
Yu. I. Grebenyuk, N. G. Kokodiy, Khe Shi
diffraction, thin cylinder, refractive index, scattering, absorption, weakening, resonance
Vestnik KhNU ¹806 Pages. 33-39
On the basis of solutions to the wave equation, the efficiency of dispersing, absorbing, and weakening the electromagnetic field that a thin cylinder with a large refractive index diffracts has been estimated. The transverse and longitudinal distribution of the electromagnetic field inside and outside of the cylinder has been calculated. The resonance is found to increase the intensity of both the electromagnetic wave field inside the cylinder and the scattered wave outside. Inside the cylinder at resonance, a wave propagating along its surface arises, and under some conditions, a wave propagating through the cylinder is also generated. As the refractive index is increased, the wave tracks the cylinder surface more closely, and its intensity is progressively enhanced.
21. The influence of a dispersion and losses to the interaction of impulse signal with the model of the biological tissues
O.N. Zheryobkina, O.V. Kazanskiy
impulse signal, a biological tissue, time domain, flatlayer dielectric, dispersion
Vestnik KhNU ¹806 Pages. 40-43
In this paper the interaction of the impulse signal with biological tissues on an example of the flatlayer dielectric that models consecutive layers a skin, fat, muscle tissue is investigated. In this model, it is taken into account dispersion of the dielectric permeability and losses in a medium. The calculation program is received in result. It accounts the space-time characteristics of the reflected and past signals for layers of the flatlayer dielectric with parameters of biological tissues. Influence of values of the dielectric permeability and angle of incidence on the characteristics of past and scattered signals also is considered.
22. CALCULATION AND MEASURING OF IMPEDANCE OF IMPATT-DIODE IN MILLIMETR WAVE
A.V. Arkhipov, V.T. Plaksiy, I.K. Kuzmichev, E.D. Prokhorov, A.V. Dydchenko, D.P. Chuechkov
millimeter wave range, impedance, IMPATT diode, conductance, susceptance
Vestnik KhNU ¹806 Pages. 59-64
The calculated and experimental results of the impedance of the impact avalanche transit-time (IMPATT) diode for the 8 millimeter wavelength range have been presented. The dependences of the IMPATT diode impedance as a function of the normalized amplitude î Ã the fundamental current harmonic of the p-n junction and frequency have been calculated and measured. The apparatus and measuring method of the conductance and susceptance of the IMPATT diode has been developed
23. Application of the digital holographic interference microscope for investigation of thin films
D.N. Tishko, T.V. Tishko, V.P.Titar, Yu. A. Zadneprovskiy, A.S. Kuprin, I.A.Zgoda
digital holographic interference microscope, three-dimensional images, vacuum-arc method, thin AlN films
Vestnik KhNU ¹806 Pages. 99-102
For the first time the digital holographic interference microscope (DHIM) was used for investigation of thin films on transparent substrates. Three-dimensional images of AlN of thin films, deposited on acryl substrates by the vacuum-arc method have been obtained, their thicknesses have been measured. It has been shown that the DHIM can be successfully used for film surface quality checking, thickness and film damages parameters measurement.
24. Earth profile plotting using pulse radar with scanning antenna array
A. S. Kutsenko, Î. V. Kazansky, N. N. Kolchigin
pulse radar, antenna array, radar image
Vestnik KhNU ¹834 Pages. 37-41
This paper is devoted to development of radar signal processing technique which allows one to reconstruct earth profile and reveal and identify manmadc objects which arc situated on underlaying surface. The technique of signal processing and image construction is based on measuring of directional characteristics of the scene being investigated. Modeling of radar activity has been performed; radar images of some simple scatterers have been obtained. Possibility of using the technique for scene profile reconstruction and revealing of manmade objects situated on it has been shown
25. Radiation of short pulses from the open end of waveguide
O.M. Dumin, O.O. Dumina, V.O. Katrich, Zheng Yu
transient field, modal basis method, evolutionary equations, impulse field irradiation
Vestnik KhNU ¹834 Pages. 63-67
The problem of transient electromagnetic field radiation from the open end of waveguide is solved in time domain by the analytical and direct numeral methods. The problem of impulse signal propagation in regular waveguide is converted to the finding of transient wave propagation operator by modal basis method. The application of the operator for the obtaining of time form of signal both for the time change in positive and in the negative direction permits to seek an arbitrary time dependence of field amplitude in any point of waveguide taking into account distortions due to wave dispersion. The correction of diffraction distortions of time form of wave and forming the short probe impulse on the waveguide aperture by the excitation of waveguide in the given cross-section by field with the previously calculated time dependence are considered . Numerical simulation of short impulse irradiation of layered medium with losses is carried out
26. Near electromagnetic field of combined waveguide-slot radiators in matter
S.L. Berdnik, V.A. Katrich, M.V. Nesterenko, S.V. Pshenichnaya
rectangular waveguide, waveguide-slot radiator, material medium, hyperthermia, Galerkin's method
Vestnik KhNU ¹834 Pages. 85-88
The problem about the electromagnetic waves radiation into the homogeneous isotropic medium by the system of combined waveguide-slot radiators in the broad wall of a rectangular waveguide has been solved in a rigorous self-consistent formulation. The spatial distribution of the near field intensity in the half-infinite material medium with the electrophysical parameters, corresponding to some man's tissues, has been investigated
27. Capacitance-voltage measurements in selectively doped ALGAAS/GAAS heterostructures
N.B.Gorev, I.F. Kodzhespirova, E.N. Privalov
gallium arsenide, selectively doped heterostructures, Schottky barrier, barrier capacitance, capacitance–voltage measurements
Vestnik KhNU ¹853 Pages. 3-7
The dependence of the measured apparent capacitance of selectively doped AlGaAs/GaAs heterostructures on the amplitude of the measuring ac voltage is calculated numerically. An expression that gives the measured apparent capacitance as a function of the true capacitance and the above amplitude is derived. Using this expression and the results of the above numerical calculation, it is shown that capacitance–voltage characteristics of selectively doped AlGaAs/GaAs heterostructures, which feature steeply dropping regions, may be measured at moderately small amplitudes of the measuring ac voltage (of the order of 100 mV) at the expense of taking measurements at two different amplitudes
28. Global Sensitivity analysis of the dipole matrix element according to variation of parameters of the indium surface segregation in ingan/gan quantum well
indium surface segregation, semiconductor nitrides, piezoelectric polarization, dipole matrix element, global sensitivity analysis
Vestnik KhNU ¹853 Pages. 8-14
In this paper, influence of the indium surface segregation on dipole matrix element for InGaN/GaN heterostructure is under investigation. The global sensitivity analysis has been applied for quantitative estimation of the indium surface segregation effect at each interface of the quantum well. Together with the indium surface segregation, the piezoelectric effects are considered. It has been shown that joint action of the piezoelectric fields and the indium surface segregation leads to changes in the selection rules for optical transitions. Results give the method to apply the optical spectroscopy for observation of the indium surface segregation
29. Algorithms of the processing signal from the trellised receiver for measuring of the laser radiation characteristics
Kokodiy N.G., Pak A.O.
the laser, optical radiation, intensity, bolometer, direct task, reverse task
Vestnik KhNU ¹853 Pages. 37-44
In this paper has been considered the development of the device for the measurement of the intensity distribution in the beam of optical radiation. The algorithm of processing of a signal from the receiver of radiation is studied. The method of measurement of the intensity distribution of optical radiation by the bolometric grid is offered. The developed algorithms for processing a signal from the measuring converter and programs realizing them are checked up experimentally, their serviceability is confirmed. The comparative characteristic of algorithms based on the transformation of Fourier and transformation of Radon has shown an opportunity of their use in practice
30. Analysis of impulse fields reflected from layered medium with losses using artificial neural network
Shyrokorad D. V., Dumin O.M., Dumina O.O., Katrich V.O.
time domain, artificial neural network, impulse fields, layered medium
Vestnik KhNU ¹883 Pages. 35-40
The problem of determination of thickness a layer of layered medium by impulse irradiation is solved. The impulse fields reflected from the layered medium with electrical characteristics close to the characteristics of human skin are analyzed by artificia
31. About convergence of the mode expansions onto spherical harmonic in time domain
Kochetov B.A., Butrym A.Yu.
mode basis method, transient field, spherical modes, ring current
Vestnik KhNU ¹883 Pages. 41-44
The convergence of spherical mode expansions in the time domain to the exact solution is shown on an example of a test problem that has a closed-form solution. Radiation of a ring with transient current in free space is considered. It was shown that there
32. Determination of optimal parameters of a magnetocardiographic hexagonal measuring grid
A.Yu. Kostiev, A.Yu. Butrym, S.N. Shulga
magnetocardiography, gradiometer, current dipole, sensitivity, Hessian
Vestnik KhNU ¹883 Pages. 25-29
The article considers hexagonal grid of gradiometer sensors of magnetic field. The aim of the study is to determine the optimal parameters of the grid and the gradiometers in order to obtain maximum sensitivity of the measuring system in terms of location
33. Ballistic electronic transport in continuous-band superlattice under applied electrostatic field
S.I.Petrov, Klymenko M. V., Shulika O. V.
ballistic transport, superlattice, effective potential
Vestnik KhNU ¹883 Pages. 12-19
We address in this work ballistic transport of electrons in semiconductor continuous-band superlattice under applied electrostatic field. Combined influence of the effective mass periodically varied in space and external electrostatic field on the electro
34. Polarization and energy characteristics X-slots in the waveguide with the complex load and the dielectric inserts
Blinova N.K., Yatsuk N.N., Selyutin A.V.
Õ-slots , ellipse coefficient, VSWR level , circular polarization.
Vestnik KhNU ¹966 Pages. 77-81
The Õ-slots in a rectangular waveguide with the end complex loading and dielectric inhomogeneity at the waveguide input are considered. Calculation and experimental results of power and polarization descriptions are carried out for such systems. The possibilities of polarization and power characteristics of Õ-slot control are investigated. The variation of dielectric inhomogeneity and complex end loading parametors allows to obtain the circular polarization, high radiation coefficient and low VSWR level
35. Impedance characteristics of planar diodes with tunnel boundaries based on GaAs
Prokhorov E.D., Botsula O.V., Klimenko O.A.
: negative differential conductivity, tunnel boundary, a diode, the tunneling.
Vestnik KhNU ¹966 Pages. 13-18
The impedance characteristics of the diodes are consider, which negative differential conductivity (NDC) is arise under cer-tain voltage, due to tunneling of electrons through the side faces of the diode, which can be used for generation, amplification and multiplication. Depending on the active and reactive components of impedance are determined of the diode with the tun-nel boundaries for the real parameters of the diodes. It is shown that the limiting frequency of the diode NDC is in the tera-hertz range and depends on its parameters.
36. Determena Frequency properties of intervalley electron transfer in AlN
V. T. Plaksiy, À.V.Arhipov, À. S. Tischenko, Ò. ². Kamishanova, E.D. Prokhorov, À.V.Dyadchenko, D. P.Chueshkov
perfect crystal, zone overcrystallization, temperature gradient
Vestnik KhNU ¹966 Pages. 19-22
The problem of growing of perfect bismuth-antimony monocrystals having of a uniform distribution of Sb atoms through the crystal by help floating-zone refining method is considered. The expression for temperature gradient in melt and temperature distribution for any melt point have been obtained.
The monocrystals growing maximal velocity have been estimated. The growing velocity must be lower then 1 mm per hour was showed. It is velocity not lead to concentration overcooling and arising inhomogeneous dendrite structure. For solution with certain composition ( at = const) overcooling may be eliminated by either increasing of temperature gradient in liquid faze or decreasing growing velocity are showed.
37. Ðåøåò÷àòûé ïðèåìíèê äëÿ èçìåðåíèé õàðàêòåðèñòèê ëàçåðíîãî èçëó÷åíèÿ
Lizogubenko S.V., Kokodiy N.G.
scattering pattern, diameter of the particles, scattering, brightness of the light spot, beam intensity
Vestnik KhNU ¹966 Pages. 9-12
Considered the method of defining the size of microparticles using a digitized image of the scattering. For research the optical method is used It consists that the researched substance, consisting of microparticles, is illuminated with the beam of optical radiation and then the scattering of the transmitted light is registered. After this, the digital processing of resulting scattering pattern is carried out and held the measurement of particle size in two different ways.
38. New statistical methods of recognition and classification for automatic interpretation of remote observations
Koltunov Y.A., Dumin O.M., Katrich V.A., Naumov R.R.
methods of recognition and classification, blenderized models of the probabilistic distributing, teaching selection
Vestnik KhNU ¹966 Pages. 37-49
Mathematical models, computational algorithms, and also prospects of development and application of three new methods of recognition and classification (RÀC), namely, construction of distinctive characteristics of objects; classification on the basis of probabilistic teaching selection with optimization of method RAC; account of dynamics of features of recognized objects are presented in the article. Recognition and classification is an area of modern science that have a boundless list of applications in all spheres of human activity. From the list of applications the only one is selected in the present work, but the most actual one, that is the remote sensing of ground surface in radiofrequency band with the purpose of study and maintainance of natural resources of Earth.
39. Signal scattering on the meteor trail
signal scattering, meteor trail, diffraction oscillations, electron density, plasma collective interaction, impulse response.
Vestnik KhNU ¹966 Pages. 90-96
A generalized model of the radiosignal scattering on the meteor trail is proposed. The model allows to take into account the process of formation and development of the meteor trail, and to calculate the scattered signal power change without sharing the meteor trails on underdense and overdense. As input parameters of the model used the physical parameters of the meteoroid - the mass and velocity, which determine the ionization of the plasma formation, as well as the location and orientation of the meteor trail. In the derivation of the analytical relations taken into account the presence of the plasma sheath surrounding the 'metal cylinder' and the collective interactions in the plasma. In the paper shown that the results of calculations are in good agreement with observations.
40. Influence of shading of the radiating aperture of single-reflector antenna by focal module on directional characteristics
Gorobets N.N., Kiyko V.I.
microwaves, reflector antennas, reflector shading, directional characteristics
Vestnik KhNU ¹966 Pages. 97-102
The effect of shading of the radiating aperture single-reflector parabolic antenna on radiation pattern, gain, wide beamwidth and sidelobe levels while changing the focal length of the relationship to the diameter of the reflector in the range of 0.5 to 1.5 takes place was theoretically investigated. Thus, it was shown that the effect of shading on all directional characteristics is the less than the longer-focused is the reflector. The minimum level of side lobes is in the case of short-focused reflector
41. The xecl laser with the adjustable shape and duration of generation pulse
S.S. Anufrik, A.P. Volodenkov, K.F. Znosko
LC- contour, XeCl laser, excitation system, generation energy, pulse duration.
Vestnik KhNU ¹983 Pages. 3-10
The generation parameters of LC-contour excitation system are studied for electro-discharge excimer XeCl laser using a Ne–Xe–HCl mixture. A computation model is developed for finding the generation parameters. It has allowed us to calculate current, voltage and generation power oscillograms for all parameters of the electrical excitation system. The program of XeCl-laser modeling enables to calculate an electrons, atom and molecule concentrations, specific energy deposition in active medium also. By means of program Bolsig + calculation of rate coefficients of reactions with participation of electrons is executed. It is shown that generation of short radiation pulses (20 ns) and relatively long pulses (60 ns) is possible due to changing of LC- contour parameters. Energy of generation reaches a maximum at use of small values of peaking capacity, which are significantly smaller then value of storage capacity.
42. Light propagation characteristics of optical metal dielectric coaxial nano-waveguides with complex shapes
O.N. Kozina, I.S. Nefedov, L.A. Melnikov
plasmonic waveguides, coaxial, noble metals, numerical simulations, nano-size.
Vestnik KhNU ¹983 Pages. 48-53
The properties of new optical waveguides with nanosize cross-section made of noble metals and glasses are described. This waveguide supports propagation of modes with unusual propagation properties. For estimation of the field localization, losses, propagation length, velocity and others characteristics the numerical simulations by FEM method has been used. Coaxial waveguide with the annular and the elliptic central rods are considered. The comparatively low value of losses has explained.
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